--from-history requires conda >=4.8.0

[zhanyuanucb]

Describe the bug
Got conda-env: error: unrecognized arguments: --from-history while running example/run_docker.sh

usage: conda-env [-h] {attach,create,export,list,remove,upload,update} ...
conda-env: error: unrecognized arguments: --from-history
ERROR: could not infer current conda environment for automatic dockerization
Traceback (most recent call last):
  File "example/../bin/pircli", line 6, in <module>
    main()
  File "/home/zhanyuan.zhang/pirlib/pirlib/cli/main.py", line 42, in main
    args.handler(args.parser, args)
  File "/home/zhanyuan.zhang/pirlib/pirlib/cli/generate.py", line 34, in _generate_handler
    package = dacite.from_dict(data_class=Package, data=yaml.safe_load(f))
  File "/home/zhanyuan.zhang/.conda/envs/pirlib/lib/python3.8/site-packages/dacite/core.py", line 59, in from_dict
    field_data = data[field.name]
TypeError: 'NoneType' object is not subscriptable
ERROR: Version in "/home/zhanyuan.zhang/pirlib/example/docker-compose.yml" is unsupported. You might be seeing this error because you're using the wrong Compose file version. Either specify a supported version (e.g "2.2" or "3.3") and place your service definitions under the `services` key, or omit the `version` key and place your service definitions at the root of the file to use version 1.
For more on the Compose file format versions, see https://docs.docker.com/compose/compose-file/
ERROR: Version in "/home/zhanyuan.zhang/pirlib/example/docker-compose.yml" is unsupported. You might be seeing this error because you're using the wrong Compose file version. Either specify a supported version (e.g "2.2" or "3.3") and place your service definitions under the `services` key, or omit the `version` key and place your service definitions at the root of the file to use version 1.
For more on the Compose file format versions, see https://docs.docker.com/compose/compose-file/

To Reproduce

1. Install conda < 4.8.0
2. run bash example/run_docker.sh

Additional context
--from-history option is only avaliable in conda>=4.8.0

pirlib/pirlib/cli/dockerize.py

Line 134 in b2d8cc9

command.append("--from-history")